相关论文: Results from AstroSat LAXPC Observations of Hercul…

We report results from long-term (approximately 1240 days) X-ray (0.3-8.0 keV) monitoring of the ultraluminous X-ray source NGC 5408 X-1 with the Swift/X-Ray Telescope. Here we expand on earlier work by Strohmayer (2009) who used only a…

We present the results of timing and spectral analysis of the HMXB pulsar, Cen X-3, with the help of observations carried out using the Large Area X-ray Proportional Counter (LAXPC) on board $\textit{AstroSat}$. As part of our analysis, we…

We study properties of the superorbital modulation of the X-ray emission of Cyg X-1. We find that it has had a stable period of about 300 d in soft and hard X-rays and in radio since 2005 until at least 2010, which is about double the…

We present the results of detailed analysis of X-ray data in 3-20 keV range from a ~70 day outburst of the neutron star transient Aquila X-1 during September-November 2000. Optical monitoring with the YALO 1m telescope was used to trigger…

The cyclotron line in the spectrum of the accretion-powered pulsar Her X-1 offers an opportunity to assess the ability of the BATSE Spectroscopy Detectors (SDs) to detect lines like those seen in some GRBs. Preliminary analysis of an…

A nonlinear nature of the binary ephemeris of Cygnus X-3 indicates either a change in the orbital period or an apsidal motion of the orbit. We have made extended observations of Cygnus X-3 with the Pointed Proportional Counters (PPCs) of…

We present the analysis of Rossi X-ray Timing Explorer (RXTE) observations of the turn-on phase of a 35 day cycle of the X-ray binary Her X-1. During the early phases of the turn-on, the energy spectrum is composed of X-rays scattered into…

DI Herculis is an eclipsing binary famous for a longstanding disagreement between theory and observation of the apsidal precession rate, which was resolved when both stars were found to be severely misaligned with the orbit. We used data…

We report the discovery of coupling between periodic and aperiodic variability and ~12-mHz X-ray quasi-periodic oscillations (QPOs) from the X-ray binary pulsar Her X-1 using data from the Rossi X-Ray Timing Explorer. We found two different…

The ultra-luminous X-ray (ULX) source ESO 243-49 HLX-1 currently provides the strongest evidence for the existence of intermediate mass black holes. We conduct an ongoing monitoring campaign with the Swift X-ray Telescope and found that…

Rapid spectral changes in the hard X-ray on a time scale down to ~0.1 s are studied by applying "shot analysis" technique to the Suzaku observations of the black hole binary Cygnus X-1, performed on 2008 April 18 during the low/hard state.…

We report on the first analysis of AstroSat observation of the Z-source GX 5- 1 on February 26-27, 2017. The hardness-intensity plot reveals that the source traced out the horizontal and normal branches. The 0.8-20 keV spectra from…

We have analyzed the time variability of the wide-band X-ray spectrum of Vela X-1, the brightest wind-fed accreting neutron star, on a short timescale of 2 ks by using {\it Suzaku} observations with an exposure of 100 ks. During the…

Below an accretion rate of approximately a few per cent of the Eddington accretion rate, X-ray binary systems are not usually found in the soft spectral state. However, at accretion rates a factor of a few lower still, in the hard state,…

We present disk wind model calculations for the broad emission lines seen in the ultraviolet spectra of the X-ray binary Hercules X-1. Recent HST/STIS observations of these lines suggest that they are kinematically linked to the orbital…

We report continuous monitoring of Cygnus X-1 in the 1.3 to 200 keV band using ASM/RXTE and BATSE/CGRO for about 200 days from 1996 February 21 to 1996 early September. During this period Cygnus X-1 experienced a hard-to-soft and then a…

We report a long-term, high-cadence timing and spectral observation of the X-ray pulsar SMC X-1 using NinjaSat, a 6U CubeSat in low-Earth orbit, covering nearly a full superorbital cycle. SMC X-1 is a high-mass X-ray binary exhibiting a 0.7…

We present a dynamical model of the high mass X-ray binary LMC X-1 based on high-resolution optical spectroscopy and extensive optical and near-infrared photometry. From our new optical data we find an orbital period of P=3.90917 +/-…

We report on spectral and timing analysis of BeppoSAX data of the 13.6 s period transient X-ray pulsar EXO 0531-6609.2. Observations were carried out in March 1997 and October 1998, catching the source during a high and a low emission…

X-ray binaries are known to launch powerful accretion disk winds that can have significant impact on the binary systems and their surroundings. To quantify the impact and determine the launching mechanisms of these outflows, we need to…